[llvm] [SPIR-V] fix return type for OpAtomicCompareExchange (PR #154297)

[Victor Lomuller via llvm-commits]

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@@ -0,0 +1,35 @@
+; RUN: llc -O0 -mtriple=spirv64-unknown-unknown %s -o - | FileCheck %s --check-prefix=CHECK-SPIRV
+; RUN: llc -O0 -mtriple=spirv64-unknown-unknown %s -o %t.spv -filetype=obj
+; RUN: spirv-val %t.spv
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Naghasan wrote:

```suggestion
; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown %s -o - -filetype=obj | spirv-val %}
```

spirv-val maybe not be available 

https://github.com/llvm/llvm-project/pull/154297